Extend the DPLL core to support associating a DPLL pin with a firmware
node. This association is required to allow other subsystems (such as
network drivers) to locate and request specific DPLL pins defined in
the Device Tree or ACPI.

* Add a .fwnode field to the struct dpll_pin
* Introduce dpll_pin_fwnode_set() helper to allow the provider driver
  to associate a pin with a fwnode after the pin has been allocated
* Introduce fwnode_dpll_pin_find() helper to allow consumers to search
  for a registered DPLL pin using its associated fwnode handle
* Ensure the fwnode reference is properly released in dpll_pin_put()

Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Signed-off-by: Ivan Vecera <ivecera@redhat.com>
---
 drivers/dpll/dpll_core.c | 49 ++++++++++++++++++++++++++++++++++++++++
 drivers/dpll/dpll_core.h |  2 ++
 include/linux/dpll.h     | 11 +++++++++
 3 files changed, 62 insertions(+)

diff --git a/drivers/dpll/dpll_core.c b/drivers/dpll/dpll_core.c
index 8879a72351561..55f3ff50a8709 100644
--- a/drivers/dpll/dpll_core.c
+++ b/drivers/dpll/dpll_core.c
@@ -10,6 +10,7 @@
 
 #include <linux/device.h>
 #include <linux/err.h>
+#include <linux/property.h>
 #include <linux/slab.h>
 #include <linux/string.h>
 
@@ -595,12 +596,60 @@ void dpll_pin_put(struct dpll_pin *pin)
 		xa_destroy(&pin->parent_refs);
 		xa_destroy(&pin->ref_sync_pins);
 		dpll_pin_prop_free(&pin->prop);
+		fwnode_handle_put(pin->fwnode);
 		kfree_rcu(pin, rcu);
 	}
 	mutex_unlock(&dpll_lock);
 }
 EXPORT_SYMBOL_GPL(dpll_pin_put);
 
+/**
+ * dpll_pin_fwnode_set - set dpll pin firmware node reference
+ * @pin: pointer to a dpll pin
+ * @fwnode: firmware node handle
+ *
+ * Set firmware node handle for the given dpll pin.
+ */
+void dpll_pin_fwnode_set(struct dpll_pin *pin, struct fwnode_handle *fwnode)
+{
+	mutex_lock(&dpll_lock);
+	fwnode_handle_put(pin->fwnode); /* Drop fwnode previously set */
+	pin->fwnode = fwnode_handle_get(fwnode);
+	mutex_unlock(&dpll_lock);
+}
+EXPORT_SYMBOL_GPL(dpll_pin_fwnode_set);
+
+/**
+ * fwnode_dpll_pin_find - find dpll pin by firmware node reference
+ * @fwnode: reference to firmware node
+ *
+ * Get existing object of a pin that is associated with given firmware node
+ * reference.
+ *
+ * Context: Acquires a lock (dpll_lock)
+ * Return:
+ * * valid dpll_pin struct pointer if succeeded
+ * * ERR_PTR(X) - error
+ */
+struct dpll_pin *fwnode_dpll_pin_find(struct fwnode_handle *fwnode)
+{
+	struct dpll_pin *pin, *ret = NULL;
+	unsigned long index;
+
+	mutex_lock(&dpll_lock);
+	xa_for_each(&dpll_pin_xa, index, pin) {
+		if (pin->fwnode == fwnode) {
+			ret = pin;
+			refcount_inc(&ret->refcount);
+			break;
+		}
+	}
+	mutex_unlock(&dpll_lock);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(fwnode_dpll_pin_find);
+
 static int
 __dpll_pin_register(struct dpll_device *dpll, struct dpll_pin *pin,
 		    const struct dpll_pin_ops *ops, void *priv, void *cookie)
diff --git a/drivers/dpll/dpll_core.h b/drivers/dpll/dpll_core.h
index 8ce969bbeb64e..d3e17ff0ecef0 100644
--- a/drivers/dpll/dpll_core.h
+++ b/drivers/dpll/dpll_core.h
@@ -42,6 +42,7 @@ struct dpll_device {
  * @pin_idx:		index of a pin given by dev driver
  * @clock_id:		clock_id of creator
  * @module:		module of creator
+ * @fwnode:		optional reference to firmware node
  * @dpll_refs:		hold referencees to dplls pin was registered with
  * @parent_refs:	hold references to parent pins pin was registered with
  * @ref_sync_pins:	hold references to pins for Reference SYNC feature
@@ -54,6 +55,7 @@ struct dpll_pin {
 	u32 pin_idx;
 	u64 clock_id;
 	struct module *module;
+	struct fwnode_handle *fwnode;
 	struct xarray dpll_refs;
 	struct xarray parent_refs;
 	struct xarray ref_sync_pins;
diff --git a/include/linux/dpll.h b/include/linux/dpll.h
index c6d0248fa5273..f2e8660e90cdf 100644
--- a/include/linux/dpll.h
+++ b/include/linux/dpll.h
@@ -16,6 +16,7 @@
 struct dpll_device;
 struct dpll_pin;
 struct dpll_pin_esync;
+struct fwnode_handle;
 
 struct dpll_device_ops {
 	int (*mode_get)(const struct dpll_device *dpll, void *dpll_priv,
@@ -178,6 +179,8 @@ void dpll_netdev_pin_clear(struct net_device *dev);
 size_t dpll_netdev_pin_handle_size(const struct net_device *dev);
 int dpll_netdev_add_pin_handle(struct sk_buff *msg,
 			       const struct net_device *dev);
+
+struct dpll_pin *fwnode_dpll_pin_find(struct fwnode_handle *fwnode);
 #else
 static inline void
 dpll_netdev_pin_set(struct net_device *dev, struct dpll_pin *dpll_pin) { }
@@ -193,6 +196,12 @@ dpll_netdev_add_pin_handle(struct sk_buff *msg, const struct net_device *dev)
 {
 	return 0;
 }
+
+static inline struct dpll_pin *
+fwnode_dpll_pin_find(struct fwnode_handle *fwnode)
+{
+	return NULL;
+}
 #endif
 
 struct dpll_device *
@@ -218,6 +227,8 @@ void dpll_pin_unregister(struct dpll_device *dpll, struct dpll_pin *pin,
 
 void dpll_pin_put(struct dpll_pin *pin);
 
+void dpll_pin_fwnode_set(struct dpll_pin *pin, struct fwnode_handle *fwnode);
+
 int dpll_pin_on_pin_register(struct dpll_pin *parent, struct dpll_pin *pin,
 			     const struct dpll_pin_ops *ops, void *priv);
 
-- 
2.52.0

> -----Original Message-----
> From: Intel-wired-lan <intel-wired-lan-bounces@osuosl.org> On Behalf
> Of Ivan Vecera
> Sent: Friday, January 30, 2026 5:54 PM
> To: netdev@vger.kernel.org
> Cc: Vadim Fedorenko <vadim.fedorenko@linux.dev>; Lobakin, Aleksander
> <aleksander.lobakin@intel.com>; Andrew Lunn <andrew+netdev@lunn.ch>;
> Kubalewski, Arkadiusz <arkadiusz.kubalewski@intel.com>; David S.
> Miller <davem@davemloft.net>; Eric Dumazet <edumazet@google.com>;
> Jakub Kicinski <kuba@kernel.org>; Jiri Pirko <jiri@resnulli.us>;
> Jonathan Lemon <jonathan.lemon@gmail.com>; Leon Romanovsky
> <leon@kernel.org>; Mark Bloch <mbloch@nvidia.com>; Paolo Abeni
> <pabeni@redhat.com>; Prathosh Satish <Prathosh.Satish@microchip.com>;
> Kitszel, Przemyslaw <przemyslaw.kitszel@intel.com>; Richard Cochran
> <richardcochran@gmail.com>; Saeed Mahameed <saeedm@nvidia.com>; Tariq
> Toukan <tariqt@nvidia.com>; Nguyen, Anthony L
> <anthony.l.nguyen@intel.com>; intel-wired-lan@lists.osuosl.org; linux-
> kernel@vger.kernel.org; linux-rdma@vger.kernel.org
> Subject: [Intel-wired-lan] [PATCH net-next v3 1/9] dpll: Allow
> associating dpll pin with a firmware node
> 
> Extend the DPLL core to support associating a DPLL pin with a firmware
> node. This association is required to allow other subsystems (such as
> network drivers) to locate and request specific DPLL pins defined in
> the Device Tree or ACPI.
> 
> * Add a .fwnode field to the struct dpll_pin
> * Introduce dpll_pin_fwnode_set() helper to allow the provider driver
>   to associate a pin with a fwnode after the pin has been allocated
> * Introduce fwnode_dpll_pin_find() helper to allow consumers to search
>   for a registered DPLL pin using its associated fwnode handle
> * Ensure the fwnode reference is properly released in dpll_pin_put()
> 
> Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
> Signed-off-by: Ivan Vecera <ivecera@redhat.com>
> ---
>  drivers/dpll/dpll_core.c | 49
> ++++++++++++++++++++++++++++++++++++++++
>  drivers/dpll/dpll_core.h |  2 ++
>  include/linux/dpll.h     | 11 +++++++++
>  3 files changed, 62 insertions(+)
> 
> diff --git a/drivers/dpll/dpll_core.c b/drivers/dpll/dpll_core.c index
> 8879a72351561..55f3ff50a8709 100644
> --- a/drivers/dpll/dpll_core.c
> +++ b/drivers/dpll/dpll_core.c
> @@ -10,6 +10,7 @@
> 
>  #include <linux/device.h>
>  #include <linux/err.h>
> +#include <linux/property.h>
>  #include <linux/slab.h>
>  #include <linux/string.h>
> 
> @@ -595,12 +596,60 @@ void dpll_pin_put(struct dpll_pin *pin)
>  		xa_destroy(&pin->parent_refs);
>  		xa_destroy(&pin->ref_sync_pins);
>  		dpll_pin_prop_free(&pin->prop);
> +		fwnode_handle_put(pin->fwnode);
>  		kfree_rcu(pin, rcu);
>  	}
>  	mutex_unlock(&dpll_lock);
>  }
>  EXPORT_SYMBOL_GPL(dpll_pin_put);
> 
> +/**
> + * dpll_pin_fwnode_set - set dpll pin firmware node reference
> + * @pin: pointer to a dpll pin
> + * @fwnode: firmware node handle
> + *
> + * Set firmware node handle for the given dpll pin.
> + */
> +void dpll_pin_fwnode_set(struct dpll_pin *pin, struct fwnode_handle
> +*fwnode) {
> +	mutex_lock(&dpll_lock);
> +	fwnode_handle_put(pin->fwnode); /* Drop fwnode previously set
> */
> +	pin->fwnode = fwnode_handle_get(fwnode);
> +	mutex_unlock(&dpll_lock);
> +}
> +EXPORT_SYMBOL_GPL(dpll_pin_fwnode_set);
> +
> +/**
> + * fwnode_dpll_pin_find - find dpll pin by firmware node reference
> + * @fwnode: reference to firmware node
> + *
> + * Get existing object of a pin that is associated with given
> firmware
> +node
> + * reference.
> + *
> + * Context: Acquires a lock (dpll_lock)
> + * Return:
> + * * valid dpll_pin struct pointer if succeeded
> + * * ERR_PTR(X) - error
> + */
> +struct dpll_pin *fwnode_dpll_pin_find(struct fwnode_handle *fwnode) {
> +	struct dpll_pin *pin, *ret = NULL;
> +	unsigned long index;
> +
> +	mutex_lock(&dpll_lock);
> +	xa_for_each(&dpll_pin_xa, index, pin) {
> +		if (pin->fwnode == fwnode) {
> +			ret = pin;
> +			refcount_inc(&ret->refcount);
> +			break;
> +		}
> +	}
> +	mutex_unlock(&dpll_lock);
> +
> +	return ret;
> +}
> +EXPORT_SYMBOL_GPL(fwnode_dpll_pin_find);
> +
>  static int
>  __dpll_pin_register(struct dpll_device *dpll, struct dpll_pin *pin,
>  		    const struct dpll_pin_ops *ops, void *priv, void
> *cookie) diff --git a/drivers/dpll/dpll_core.h
> b/drivers/dpll/dpll_core.h index 8ce969bbeb64e..d3e17ff0ecef0 100644
> --- a/drivers/dpll/dpll_core.h
> +++ b/drivers/dpll/dpll_core.h
> @@ -42,6 +42,7 @@ struct dpll_device {
>   * @pin_idx:		index of a pin given by dev driver
>   * @clock_id:		clock_id of creator
>   * @module:		module of creator
> + * @fwnode:		optional reference to firmware node
>   * @dpll_refs:		hold referencees to dplls pin was
> registered with
>   * @parent_refs:	hold references to parent pins pin was registered
> with
>   * @ref_sync_pins:	hold references to pins for Reference SYNC
> feature
> @@ -54,6 +55,7 @@ struct dpll_pin {
>  	u32 pin_idx;
>  	u64 clock_id;
>  	struct module *module;
> +	struct fwnode_handle *fwnode;
>  	struct xarray dpll_refs;
>  	struct xarray parent_refs;
>  	struct xarray ref_sync_pins;
> diff --git a/include/linux/dpll.h b/include/linux/dpll.h index
> c6d0248fa5273..f2e8660e90cdf 100644
> --- a/include/linux/dpll.h
> +++ b/include/linux/dpll.h
> @@ -16,6 +16,7 @@
>  struct dpll_device;
>  struct dpll_pin;
>  struct dpll_pin_esync;
> +struct fwnode_handle;
> 
>  struct dpll_device_ops {
>  	int (*mode_get)(const struct dpll_device *dpll, void
> *dpll_priv, @@ -178,6 +179,8 @@ void dpll_netdev_pin_clear(struct
> net_device *dev);  size_t dpll_netdev_pin_handle_size(const struct
> net_device *dev);  int dpll_netdev_add_pin_handle(struct sk_buff *msg,
>  			       const struct net_device *dev);
> +
> +struct dpll_pin *fwnode_dpll_pin_find(struct fwnode_handle *fwnode);
>  #else
>  static inline void
>  dpll_netdev_pin_set(struct net_device *dev, struct dpll_pin
> *dpll_pin) { } @@ -193,6 +196,12 @@ dpll_netdev_add_pin_handle(struct
> sk_buff *msg, const struct net_device *dev)  {
>  	return 0;
>  }
> +
> +static inline struct dpll_pin *
> +fwnode_dpll_pin_find(struct fwnode_handle *fwnode) {
> +	return NULL;
> +}
>  #endif
> 
>  struct dpll_device *
> @@ -218,6 +227,8 @@ void dpll_pin_unregister(struct dpll_device *dpll,
> struct dpll_pin *pin,
> 
>  void dpll_pin_put(struct dpll_pin *pin);
> 
> +void dpll_pin_fwnode_set(struct dpll_pin *pin, struct fwnode_handle
> +*fwnode);
> +
>  int dpll_pin_on_pin_register(struct dpll_pin *parent, struct dpll_pin
> *pin,
>  			     const struct dpll_pin_ops *ops, void *priv);
> 
> --
> 2.52.0

Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>